no high molecular weight bands seen.. know to be present.. - where did they go.. in a gradeint gel? (May/18/2008 )

hii alll..
my size exclusion chromatography.. shows high moelcular wieght species of a protein present.. i mean dimer. trimer, and other higher. but no high molecular weight bands r seen on my gradient sds-page gel with stacking of course. main monomer band is seen. where did they go.

the amounts of the species on SEC is high enough to be seen on sds-page. also.. the marker.. which has bands of higher molecular weight is well resolved on the gell.. so the run is fine.
what could be with the sample? there were no visible precipitates too..
thanks!

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did you use reducing condition? SDS may also overcome noncovalent interactions that stablize the multimers .

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no.. i obviously used a non-reducing condition.. any other reasons?
thanks!

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did you use reducing conditions in the gel (bme or dtt)? it is not obvious that you used non-reducing conditions with your gel since reducing conditions are standard for sds-page and you did not specify otherwise.

your high mw proteins were, most likely, multiple subunit proteins and are probably showing up as lower mw bands.

did you see any banding in the sds-page with the high mw fractions of your column?

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